摘要
采用粉末冶金工艺制备出一种具有细小组织的Ti-6Al-3Mo-1Zr合金,通过X射线衍射仪、扫描电镜及拉伸试验等研究了热压烧结温度对该合金微观组织和力学性能的影响.结果表明:在烧结温度1000 ℃ 下制备的Ti-6Al-3Mo-1Zr合金具有细小组织和较优的力学性能,其原始β晶粒尺寸、α集束尺寸和α片层厚度分别为176 μm、49 μm和1.49 μm,室温抗拉强度、屈服强度和断后伸长率分别为895 MPa、823 MPa和12.7%,强化机制主要为固溶强化、Hall-Petch效应和α/β界面强化.由于Mo元素可降低钛合金的高温扩散系数,因此,Ti-6Al-3Mo-1Zr合金的原始β晶粒尺寸、α集束尺寸和α片层厚度均小于相同工艺条件下制备的Ti-6Al-4V合金,其室温及高温强度、加工硬化率和塑性均优于Ti-6Al-4V合金.
Abstract
A Ti-6Al-3Mo-1Zr titanium alloy with fine microstructure was prepared by powder metallurgy.The effects of different hot pressed sintering temperatures on the microstructure and mechanical properties of this alloy were studied through X-ray diffraction,scanning electron microscopy,tensile testing,and so on.The results show that Ti-6Al-3Mo-1Zr alloy prepared at a sintering temperature of 1000 ℃ exhibits fine microstructure and superior mechanical properties,and the size of prior β grain,α colony and the thickness of α lamellar are 176 μm,49 μm,and 1.49 μm,respectively.The ultimate tensile strength,yield strength and elongation at room temperature are 895 MPa,823 MPa and 12.7%,respectively.The strengthening mechanisms mainly include solid solution strengthening,Hall Petch effect and α/β interface strengthening.Due to the fact that Mo element can reduce the high temperature diffusion coefficient of titanium alloy,the size of prior β grain,α colony and the thickness of α lamellar of Ti-6Al-3Mo-1Zr alloy are smaller than those of Ti-6Al-4V alloy prepared under the same process conditions,and its strength,work hardening rate,and elongation at room temperature and high temperature are better than those of Ti-6Al-4V alloy.
基金项目
国家重点研发计划(2020YFB2008300)
国家重点研发计划(2020YFB2008301)
国家重点研发计划(2020YFB2008305)
广东省自然科学基金(2023A1515011569)
维普
万方数据